As Ralph said, "...there is an increase in apparent sharpness."



Leonard Evens has written about apparent sharpness here and there, and while the mathematics eludes me at times, I know he's right: with even a little skill in Photoshop's unsharp mask, my digital prints are so "apparently" sharp, it's nuts.



I'm not at all surprised that a straight enlargement appears less sharp than a scan with post-processing - and that without enormous effort, the lab couldn't match your digital adjustments to contrast and tonality.



A lot of brilliant mathematicians, artists, photographers, and computer engineers worked hard to make Photoshop possible. That's why I shoot large format film, and then scan it, correct it in Photoshop, and print digitally.